NFS: Clean up cache validity checking

Consolidate the open-coded checking of NFS_I(inode)->cache_validity
into a couple of helper functions.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

3 files changed, 34 insertions, 22 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 64c11f399b3d..599a602cb2fd 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -101,21 +101,11 @@ EXPORT_SYMBOL_GPL(nfs_file_release);
 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
 {
         struct nfs_server *server = NFS_SERVER(inode);
-        struct nfs_inode *nfsi = NFS_I(inode);
-        const unsigned long force_reval = NFS_INO_REVAL_PAGECACHE|NFS_INO_REVAL_FORCED;
-        unsigned long cache_validity = nfsi->cache_validity;
-
-        if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) &&
-            (cache_validity & force_reval) != force_reval)
-                goto out_noreval;
 
         if (filp->f_flags & O_DIRECT)
                 goto force_reval;
-        if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
-                goto force_reval;
-        if (nfs_attribute_timeout(inode))
+        if (nfs_check_cache_invalid(inode, NFS_INO_REVAL_PAGECACHE))
                 goto force_reval;
-out_noreval:
         return 0;
 force_reval:
         return __nfs_revalidate_inode(server, inode);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 2fc237cd338e..e3194aa797f7 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -160,6 +160,36 @@ int nfs_sync_mapping(struct address_space *mapping)
         return ret;
 }
 
+static bool nfs_check_cache_invalid_delegated(struct inode *inode, unsigned long flags)
+{
+        unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
+
+        /* Special case for the pagecache or access cache */
+        if (flags == NFS_INO_REVAL_PAGECACHE &&
+            !(cache_validity & NFS_INO_REVAL_FORCED))
+                return false;
+        return (cache_validity & flags) != 0;
+}
+
+static bool nfs_check_cache_invalid_not_delegated(struct inode *inode, unsigned long flags)
+{
+        unsigned long cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
+
+        if ((cache_validity & flags) != 0)
+                return true;
+        if (nfs_attribute_timeout(inode))
+                return true;
+        return false;
+}
+
+bool nfs_check_cache_invalid(struct inode *inode, unsigned long flags)
+{
+        if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
+                return nfs_check_cache_invalid_delegated(inode, flags);
+
+        return nfs_check_cache_invalid_not_delegated(inode, flags);
+}
+
 static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
 {
         struct nfs_inode *nfsi = NFS_I(inode);
@@ -1116,17 +1146,8 @@ static int nfs_invalidate_mapping(struct inode *inode, struct address_space *map
 
 bool nfs_mapping_need_revalidate_inode(struct inode *inode)
 {
-        unsigned long cache_validity = NFS_I(inode)->cache_validity;
-
-        if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ)) {
-                const unsigned long force_reval =
-                        NFS_INO_REVAL_PAGECACHE|NFS_INO_REVAL_FORCED;
-                return (cache_validity & force_reval) == force_reval;
-        }
-
-        return (cache_validity & NFS_INO_REVAL_PAGECACHE)
-                || nfs_attribute_timeout(inode)
-                || NFS_STALE(inode);
+        return nfs_check_cache_invalid(inode, NFS_INO_REVAL_PAGECACHE) ||
+                NFS_STALE(inode);
 }
 
 int nfs_revalidate_mapping_rcu(struct inode *inode)
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 6b79c2ca9b9a..09ca5095c04e 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -381,6 +381,7 @@ extern int nfs_drop_inode(struct inode *);
 extern void nfs_clear_inode(struct inode *);
 extern void nfs_evict_inode(struct inode *);
 void nfs_zap_acl_cache(struct inode *inode);
+extern bool nfs_check_cache_invalid(struct inode *, unsigned long);
 extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);
 extern int nfs_wait_atomic_killable(atomic_t *p);